Max Battery Charge

[Glamper1]

With full optimal sun and house switch in the off position,
what should the max charge in voltage get to?

[Protagonist]

Originally Posted by Glamper1

With full optimal sun and house switch in the off position, what should the max charge in voltage get to?

A 12v battery has a 100% charge state at approximately 12.7 volts.

If you want to check the true state of charge from the display for your solar charge controller, check in the middle of the night, because during the day it might be showing the charging voltage rather than the battery voltage.

[73shark]

I don't think I've ever seen mine above 13V and max charge current at 3.2 amps.

[AtomicNo13]

My morningstar mppt will occasionally charge at 14.5. Volts then drop to 13ish....

[lewster]

If you have a 3-stage charging system, you should see between 14.2 up to 14.6VDC in the bulk and absorption charging phases. This voltage is totally dependent on the battery type and charger's potential output, and charge programming. Magnum inverter/chargers can be programmed for voltage profiles that perfectly suit different battery types.....converters can not.

After the battery approaches full, the voltage should then drop to 'float' which also differs with battery type, but usually hovers between 13.2-13.4. LiPo batteries (ours specifically) float at 13.5VDC.

All battery manufacturers have definite specifications for their batteries. Some are full at 12.6VDC, others at 12.8-13.2VDC and still others at 13.5VDC. There is no universal number, as each battery has it's own voltage profiles.

[73shark]

FWIW, I think the OP was looking at what the solar system max voltage was.

[AtomicNo13]

Regulated voltage is going to be similar to the charging algorithm of a good 4 stage regulator..... 14.5 down to 13 and change..... Some selectable for agm batteries or wet cell.

[lewster]

Yep. Quality solar controllers are either programmable (Blue Sky and Morningstar) or have selectable charge profiles c


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

[Mrjkq]

To maintain my batteries while in storage I purchased a Schumacker portable solar charger, it's the perfect size to place on top of the LP box while alligator clipped to the batteries for maintaining the charge, it has an optional control to prevent overcharging & seems to work well while held in place by a few bongie cords.